:)))

FT(sinc(x)) becomes zero at lots of points, isn't it?
　
来源: career 于 2015-03-07 07:06:36 [档案] [转至博客] [旧帖] [给我悄悄话] 本文已被阅读：1 次 (53 bytes)
字体：调大/重置/调小 | 加入书签 | 打印 | 所有跟帖 | 加跟贴 | 当前最热讨论主题 | 编辑 | 删除
回答: Bochner calls it "positive definite", not "NND". Get a better te 由 weston 于 2015-03-07 06:56:21
So it's non-negative definite.

:)

所有跟帖： 

• Instead of spitting nonsense here, you should go to understand B -weston- ♀ (39 bytes) () 03/07/2015 postreply 09:08:04

• More likely, you misquoted that guy. :) -career- ♂ (64 bytes) () 03/07/2015 postreply 09:18:39

• Your memory of constructing positive definite funciton is failin -weston- ♀ (101 bytes) () 03/07/2015 postreply 09:41:18

• You forgot any integral over a zero-valued set yields zero. :) -career- ♂ (62 bytes) () 03/07/2015 postreply 11:19:23

• No. But the integral takes place over the entire space. Silly -weston- ♀ (0 bytes) () 03/07/2015 postreply 11:22:38

• Then look at your insisting on including the zero-valued subspac -career- ♂ (125 bytes) () 03/07/2015 postreply 11:29:43

• You learned Fourier by skipping all non-zero values of a functio -weston- ♀ (0 bytes) () 03/07/2015 postreply 11:42:21

• Show me where I did that? :) -career- ♂ (0 bytes) () 03/07/2015 postreply 11:48:47

• Out of (-.5, 0.5), rect's Lebesgue measure is zero:) -career- ♂ (200 bytes) () 03/07/2015 postreply 12:16:05

• Repeat one more time: Go and study Bochner Theorem (actually -weston- ♀ (35 bytes) () 03/07/2015 postreply 12:26:42

• Bochner/ Lebesgue won't CYA :) -career- ♂ (813 bytes) () 03/07/2015 postreply 12:40:48

• Gave you the math definition already. Your comment adds nothing -weston- ♀ (0 bytes) () 03/07/2015 postreply 13:07:01

• Got your "Say it the 3rd time, rec funcition is a step function. -career- ♂ (80 bytes) () 03/07/2015 postreply 13:10:25

• Too bad, you can't read math -weston- ♀ (0 bytes) () 03/07/2015 postreply 14:22:16